Furyk finished at eight-under 272 and won by a stroke over Luke Donald, who also had a 70 on Sunday.
PGA Tour win of the season, which was a first in his career, but the big win was the year-long FedEx Cup race. He pocketed $10 million for winning the FedEx Cup and the magnitude was not lost on Furyk.
In miserable, rainy conditions, Furyk turned his cap backward on 18 so the raindrops wouldn't impact his ball. He kicked in his short par save after blasting out of a greenside bunker, then the normally reserved Furyk unleashed a huge fist pump.
He won the fourth FedEx Cup in history and joined Tiger Woods and Vijay Singh in that elite category. This third win and the accompanying FedEx Cup title probably gave Furyk an edge on the Player of the Year race as well.
Donald finished third in the final FedEx Cup tally.
Matt Kuchar, who came into East Lake first in playoff points, never got on track all week. He finished with a one-over 71 on Sunday, tied for 25th place and came in second to Furyk in the FedEx Cup.
Retief Goosen shot a one-over 71 and took third at the Tour Championship. The two-time U.S. Open winner came in at six-under 274.
Paul Casey had a chance to win the FedEx Cup even if Furyk won the tournament. Casey came into the week fifth in playoff points, but he needed a solo second to win the FedEx Cup if Furyk captured the Tour Championship.
Casey bogeyed the 17th en route to a one-under 69. He tied for fifth with Nick Watney, who posted a three-under 67 on Sunday. The pair finished at five-under 275.
Last year's winner Phil Mickelson struggled to a four-over 74 on Sunday and tied for 22nd place at plus-three.